# Are the raw scores of the NEO-PI-R normally distributed?

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Scoring the NEO-PI-R test results, as done for example in this document, involves converting an absolute score to a t-score. However, the conversion from absolute score to t-score (as can be seen in the document above and many others) seems to be always linear, i.e. $$t=alpha*raw+eta$$ for some values of $$alpha,eta$$.

Since the t-scores are normally distributed, such a linear conversion only makes sense if the raw scores are also normally distributed (and not e.g. skew in either direction). In a limited sample that I took, I noticed that some of the facets are not normally distributed, in the sense that they have a significant amount of skewness.

Is this not a flaw in the scoring system? Or is there a (psychological) reason why we should not worry about this?

Generally, psychological scales that are the sum of forced-choice items exhibit skew as the mean approaches the floor or ceiling of the scale.

The test manual for the NEO-PI shows the exact relationship between raw scores for domains and facets and corresponding percentiles. So if you want to be more precise and not assume normality, you can use that data.

Here's one table showing skewness values in an officer sample from Detrick & Chibnall (2013). As is typical with this kind of data, there's a little bit of skew, but it's not huge. So the normal approximation wont be too bad.

Detrick, P., & Chibnall, J. T. (2013). Revised NEO Personality Inventory normative data for police officer selection. Psychological Services, 10(4), 372.

Several studies have demonstrated that religiosity is associated with specific personality traits, such as high Agreeableness/Conscientiousness or low Psychoticism. However, this evidence emerged by investigating active churchgoers with high religious practice or clerical individuals using Eysenck's taxonomy. This study explores, for the first time, personality profiles in Priests ordained by the Roman Catholic Church (N = 200) using the Five-Factor Model of personality in an Italian population. Priests were compared with demographically matched non-clerical with high religious practices (HRP, N = 301) and non-religious men (NR, N = 213).

Analysis of variance demonstrated that both Priests and HPR men shared similar personality traits, such as higher Agreeableness, lower Extraversion–excitement seeking and Openness, with respect to NR. However, Priests have distinct traits, such as the highest values of Agreeableness and the lowest Neuroticism sub-facets of angry hostility and impulsiveness, in comparison with other groups. Finally, although high Conscientiousness characterized both the Priest and HRP groups, surprisingly, we found that this psychological trait was only more evident in the latter group. Differences in religious order would seem to influence this trait.

This study demonstrates that Priests' personality differ from those of HRP men, although some important personality (sub-) facets are similar.

## Open Research

This article earned Open Data and Open Materials badges through Open Practices Disclosure from the Center for Open Science: https://osf.io/tvyxz/wiki. The data and materials are permanently and openly accessible at https://osf.io/t5v34/. The scale is available via this link: https://gosling.psy.utexas.edu/scales-weve-developed/ten-item-personality-measure-tipi/. The statistical program is available to download via this link: https://sites.psu.edu/zitaoravecz/downloads/. Author's disclosure form may also be found at the Supporting Information in the online version.

Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.

## Personality and attempted suicide in depressed adults 50 years of age and older: A facet level analysis ☆

We examined the contribution of personality traits to attempted suicide, the number of suicidal attempts, and suicidal ideation in a sample of depressed inpatients. Personality was assessed via the Revised NEO Personality Inventory (NEO-PI-R). Bivariate analyses showed that suicide attempters were more self-conscious, self-effacing, impulsive, and vulnerable to stress, and less warm, gregarious, and inclined to experience positive emotions. Multivariate regression analyses controlling for age, gender, severity of depression, and psychiatric comorbidity showed that patients with a lifetime history of attempted suicide were less inclined to experience positive emotions and be more self-effacing. Patients with more severe suicidal ideation were less warm and more self-effacing. Results indicated that specific personality traits confer risk for suicidal behaviors in middle age and older adults. Interventions tailored to specific personality profiles in this high-risk group should be developed, and their efficacy examined.

## Are the raw scores of the NEO-PI-R normally distributed? - Psychology

Psychology
Vol.5 No.4(2014), Article ID:44430,8 pages DOI:10.4236/psych.2014.54041

Prolonged Abstinence and Changes in Alcoholic Personality: A NEO PI-R Study

Isabelle Boulze 1* , Michel Launay 1 , Bertrand Nalpas 2

1 Laboratory EA4556 Epsylon, Dynamics of Human Abilities & Health Behaviors, Department of Medicine, Subject and Society Sciences, Sport Sciences, University of Montpellier and St-Etienne, Montpellier, France

2 Inserm Département d’Information Scientifique et de Communication (DISC), Service de Médiation Scientifique, Mission Inserm Associations, Paris, France

Received 22 January 2014 revised 23 February 2014 accepted 19 March 2014

Many studies have examined the risk factors for relapse in alcohol-dependent patients within the first year of treatment, and have generally focused on two personality dimensions: emotional instability and difficulty in establishing relationships. In this study, we examine if these weaknesses remain in prolonged alcohol abstinence. To do so, we administer the NEO PI-R to two groups of subjects. Group 1, Inactive Drinkers (ID), consists of 51 patients with at least two years of abstinence (average length of abstinence for this group is 6.2 years) Group 2, Recently Detoxified Drinkers (RDD), comprises 93 patients who have recently ceased consuming alcohol. Based on NEO PI-R scores, our results evidence that inactive drinkers experience significant reduction in emotional instability and improvement in relationships to others. We further observe that, with long-term abstinence, these personality dimensions normalize, ceasing to be risk factors for relapse. Additionally, we find that this long-term amelioration of traits altered by alcohol amounts to an improved behavioral adaptation to life events rather than an actual change in personality.

Keywords:Alcoholism Neo Pi-R Personality Abstinence Emotional Stability Relationship to Others

Alcohol dependence is a chronic disease characterized by a high rate of relapse following withdrawal indeed, one year after detox, prolonged abstinence is achieved by only 20% to 30% of patients, while others return to heavy drinking, either occasionally or regularly (Hayashida et al., 1989 Gual et al., 1999). This high relapse rate is generally related to several medical or social causes, and traceable mainly to psychological defects. Restoring healthy emotions management is therefore one of the keys to prolonging abstinence. To be effectively established, self-defense strategies against challenging situations require adaptive modifications of personality traits. Few studies on personality changes related to alcohol withdrawal have been conducted (Mischel, 1968 Mac Adams, 1992 Bottlender & Soyka, 2005) none of them have evidenced any significant, stable change, except for an improvement in emotional stability (Coëffec, 2011). Personality is defined as “the set of stable emotional and dynamic characteristics conditioning the personal modalities of reaction against a specific situation” (Bloch, 1999). A convenient instrument for analyzing personality is the Revised NEO Personality Inventory (NEO PI-R Costa & McCrae, 1992 NEO PI-R questionnaire Coëffec, 2011). This widely-used tool was validated with different populations (Pleasant et al., 2009) and the results showed good concordance agreement (Coëffec, 2011).

Patients with alcohol problems who were administered the NEO PI-R generally obtained a high “neuroticism” score (emotions, stress), associated with a low “agreeableness” score (relationship to others Loukas et al., 2000). In the same vein, low “conscientiousness” scores (determination) were reported in patients who had abstained from alcohol for short periods (6 months to 1 year Coëffec, Romo, & Strika, 2009 Martin & Sher, 1994 McCormick et al., 1998 Repetti et al., 2002). These data originally resulted from cross-sectional studies on alcoholic patients, and were later confirmed in a longitudinal study with a 6-month to 12-month follow-up (Bottlender & Soyka, 2004). Conclusions converged, and the authors identified a common psychological profile for alcoholic subjects regardless of personal circumstances moreover, these common psychological traits appeared to be stable through time, at least up to 12 months after alcohol consumption cessation.

Long-term, definitive abstinence remains a realistic objective for alcoholic patients, even if only a small proportion of them may achieve it. We therefore asked whether personality changes might occur long after alcohol withdrawal. To answer this question, we analyzed NEO PI-R personality traits in patients having achieved long-term abstinence, and compared them to those of newly detoxified patients.

Two groups of subjects were assembled from a pool of volunteer patients. Inclusion criteria were: age 18 years and over, ability to speak and understand French exclusion criteria were: active drug consumption, opiate substitution treatment, serious psychiatric comorbidity (psychosis, bipolarity, severe depression, generalized anxiety disorder) or life-threatening organic pathology.

The first group consisted of previously alcohol-dependent subjects who had been rigorously abstinent for at least two years. They were recruited from alcohol treatment centers or self-help groups, and were referred to as “Inactive Drinkers” (ID). The second group consisted of individuals who consulted for alcohol detoxification either for the first time, or following a relapse after a break of at least 6 months this group was named “Recent Detox Drinkers” (RDD). Patients were recruited from seven clinics specialized in the treatment of addictions, located in the French Languedoc-Roussillon cities of Bagnols-sur-Cèze, Beziers, Grau-du-Roi, Montpellier, Narbonne, Nîmes and Vigan. To prevent gender bias, inclusion in the ID group was predicated on a sex ratio of two males to one female, as is usually prevalent in treatment centers for addiction to alcohol.

2.2. Materials and Procedure

All selected subjects were interviewed face-to-face by our researcher. Socio-demographic, medical and alcohol addiction data were collected through interviews and supplemented when necessary with medical records. Data included sex, marital status, socio-professional category, employment status, education level, quantity and length of alcohol consumption, number of prior treatments, history of hospitalization in psychiatry units and severity of associated pathologies. Alcohol dependence was assessed with the ICD-10 (1992).

Psychological data were collected using the self-administered NEO PI-R personality questionnaire (Costa & McCrae, 1998, 2004). Based on advanced factor analysis (Cattell, 1996 Costa & McCrae, 1998 Hogan, 2007 Hough & Ones, 2003), this questionnaire includes 240 questions, exploring five personality domains with six facets each (Table 1).

The five domains are Neuroticism or Emotional Stability, Extraversion, Openness to Experience, Agreeableness (or Usability) and Conscientiousness (or Reliability). The analysis can be refined using data obtained with the 30 facets of these five key domains.

The NEO PI-R provides a self-scoring answer sheet: summing the raw scores for the item facets and for the main domains yields an overall score. Raw scores are then converted into standard scores. A graphic representation of the overall results can also be made to obtain an individual profile. According to Costa and McCrae (2005), personality traits are distributed in a Gaussian mode across 5 levels: very low (T ≤ 34), low (34 ≤ T ≤ 44), medium (45 ≤ T ≤ 55), high (56 ≤ T ≤ 65), very high (T > 65) the scores must then be interpreted as indicators of personality traits without pathological significance.

To ensure the anonymity and confidentiality of the data, subjects were identified solely by an inclusion number and their location source.

Quantitative data were analyzed using mean, standard deviation and median, and compared with the Student’s t-test, or Wilcoxon T test when necessary qualitative data were assessed with frequency and percentiles, and compared with the Chi Square Test or Fisher’s Exact Test. Statistical analysis was performed using STATISTICA © Version 7.1 software.

The ID group numbered 51 subjects the RDD group totaled 93. Their main characteristics are shown in Table 2. Mean age was significantly higher in the ID group than in the RDD group, F(1, 139) = 27.8, p .05. The proportion of retirees was higher (37.2% vs. 11.8%) and that of the unemployed was lower (7.8% vs. 19.3%) in the ID group than in the RDD group. No difference between groups was observed regarding sex ratio, marital status, socio-economic status or education level (Table 2).

The average length of abstinence in the ID group was 6.2, SD: 4.1 years (from two years to 17 years of abstinence see Table 3). The average number of years of heavy drinking was significantly higher in the ID group than in the RDD group, F(1, 116) = 8.49, p = .004, and so was the number of previous treatments. In contrast, ID subjects reported significantly fewer alcohol-related diseases than RDD subjects (17.6% vs. 32.2%, X2 with 4, df = 15.76, p = 0.03). Nearly two thirds of patients in both groups reported a family history of alcoholism. Just over a quarter (26%) of ID subjects reported having registered in psychiatric hospitals in the past, against 14% of RDD subjects however, the difference was not statistically significant.

NEO PI-R standard note (T) results for both ID and RDD groups are presented in Table 4 the corresponding

Table 1 . NEO PI-R domains and associated facets (McCrae et al., 1998).

Table 2 . Socio-demographic characteristics of Inactive Drinkers (ID) and Recently Detoxified Drinkers (RDD).

Table 3 . Length of abstinence, alcohol consumption, and family history of alcoholism of Inactive Drinkers (ID) and Recently Detoxified Drinkers (RDD).

Table 4 . T score means and standard deviations of Inactive Drinkers (ID) and Recently Detoxified Drinkers (RDD) for each NEO PI-R domain.

personality profiles are shown in Figure 1. Inactive drinkers displayed a “medium” NEO PI-R profile: their neuroticism, agreeableness and conscientiousness scores were in the upper part of the medium range their

Figure 1 . NEO PI-R profiles of Inactive Drinkers (ID) and Recently Detoxified Drinkers (RDD).

extraversion and openness scores were in the lower part. Recently detoxified drinkers obtained scores similar to those of the ID group subjects for extraversion (m: 46.9, SD: 8.9 vs. m: 48.6, SD: 8.5, NS) and openness (m: 47.0, SD:10.6 vs. m: 47.1, SD: 8.8, NS) however, they scored in the high range of the usual neuroticism value and their score (m: 58.2, SD: 8.7) was significantly (p = 0.0001) higher than that of inactive drinkers (m: 51.8, SD: 10.1) conversely, although in the medium range, RDD scores for agreeableness and conscientiousness were significantly lower than ID scores (m: 49.7, SD: 9 vs. m: 53.2, SD: 9.2, p = 0.03 and m: 46.6, SD: 10.3 vs. m: 52.2, SD: 8.5, p = 0.001, respectively).

The three domains in which ID and RDD exhibited significant differences (i.e., neuroticism, agreeableness and conscientiousness) were further analyzed according to their facets. Neuroticism was assessed with anxiety, anger-hostility, depression, self-consciousness, impulsiveness, and vulnerability to stress ID and RDD subjects differed significantly on five of those traits, but scored similarly on self-consciousness. For conscientiousness, ID and RDD subjects differed significantly on 4 facets: competence, sense of duty, self-discipline and deliberation however, they did not differ on achievement striving and order. Finally, for agreeableness, ID and RDD subjects differed significantly on modesty, but scored similarly on trust, straightforwardness, altruism, compliance and tender mindedness.

This study aimed to examine whether personality traits are modified during prolonged abstinence in formerly alcohol-dependent patients. To do so, we administered the NEO PI-R questionnaire to long-term abstinent subjects (inactive drinkers) and recently detoxified patients (recently detoxified drinkers). NEO PI-R scores indicated that inactive drinkers differed significantly from recently detoxified ones in three personality domains: neuroticism (p = .001), agreeableness (p = .029) and conscientiousness (p = .001). In other words, these domains are discriminative.

Regarding neuroticism, we found that inactive drinkers do not necessarily focus on negative issues. They are not shy in the presence of others and remain in control of their emotions, thusly handling frustrations better (thereby enhancing their ability to remain abstinent). Inactive drinkers are able to cope with stress and manage challenging situations without letting their emotions overrun them. Conversely, recently detoxified drinkers scored high on neuroticism (58.2). They experience difficulty in adjusting to events, a dimension which is associated with emotional instability (stress, uncontrolled impulses, irrational ideas, negative affect). Socially, they tend to isolate themselves and to withdraw from social relationships, preferring instead a hedonistic lifestyle, as suggested by several authors (McCrae et al., 1986). These results matched those found the literature (Loukas et al., 2000).

Regarding agreeableness (which ties back into social relationships), we found that inactive drinkers care for, and are interested in, others (altruism) they consider that helping others may lead to receiving help in return. Instead, recently detoxified drinkers’ low self-esteem and narcissism prevent them from enjoying interpersonal exchanges, and lead them to withdraw from social relationships.

Finally, regarding conscientiousness, we observed that, over time, inactive drinkers become more social, enjoy higher self-esteem (Costa, McCrae, & Dye, 1991), care for and are interested in others, and wish to help them (with the assumption that they will receive help in return). They are able to perform tasks without being distracted, and carefully consider their actions before carrying them out their determination remains strong regardless of the level of challenge, and their actions are guided by ethical values. Instead, recently detoxified drinkers lack confidence, rush into action, prove unreliable and unstable. As a result, lacking sufficient motivation, they experience difficulty in achieving their objectives.

Hence, in the above psychology domains, our results evidenced significant differences between the two groups. Inactive drinkers seem less nervous, less angry, less depressed, less impulsive and less vulnerable than recently detoxified drinkers. Inactive drinkers’ level of competence, sense of duty, self-discipline and ability to think before acting increases with time. While previous studies have generally focused on shorter lengths of abstinence (Martin & Sher, 1994 McCormick et al., 1998 Repetti et al., 2002 Bottlender & Soyka, 2004), ours differed in that it examined long-term abstinent subjects (2 years or more) and revealed a marked improvement in specific domains over time. Indeed, these results are quite encouraging for alcoholic patients, who may aspire to greater quality of life through long-term abstinence.

However, in spite of marked differences between groups, our results did not provide clear evidence of personality changes. While significant behavior differences between the two groups were revealed, they were more akin to long-term improvements in behavorial adequacy to events than to actual personality changes. Indeed, upon examination of the scores’ distribution across the 5 personality domains, we observed that it lied in the same medium range (45 ≤ T ≤ 55) for 4 of them neuroticism scores were the only ones to “normalize”, i.e., to move from a high level for recently detoxified drinkers to a medium level for inactive drinkers. These observations underscore the non-pathological nature of the psychological issues affecting alcoholic patients, and the latter’s potential for stabilization over time by overcoming previous behavior weaknesses. Hence, this process is not one of personality change, but rather one of better adequacy of behavior responses to reality and its changing parameters.

Several significant elements were highlighted in our study. First, it evidenced the psychological differences between inactive drinkers and recently detoxified drinkers. Second, it noted the absence of predictors of short-term or long-term success of abstinence at the time of initial treatment request. Indeed, neither did socio-demographic factors, nor the bulk of the anamnesis data, nor even personality factors seem to allow prognosis. Third, it revealed that treatment-induced behavior changes showed a decrease in neuroticism and an increase in traits related to responsibility and conscientiousness. These trends could eventually provide the basis for predictors of success of abstinence treatments.

When interpreting our results, one must remain aware that our study was not longitudinal, but based instead on the cross-comparison of two independent groups. Nonetheless, the results suggest that alcoholic patients (excluding those suffering from major psychiatric pathologies—see our exclusion criteria) possess personal traits similar to those of the general population, except for heightened neuroticism shortly after alcohol consumption cessation. In fact, these results undermine the persistent notion that alcoholic patients exhibit specific vulnerability factors. Abstinence seems associated with a behavioral improvement to adequately respond to life events, but without making actual personality modifications. These observations underscore the non-pathological nature of the psychiatric issues facing alcoholic patients and the latter’s potential for stabilization over time by overcoming previous behavioral weaknesses.

Our results, obtained from a sample of over one hundred subjects, therefore suggest that the personality of alcoholic patients remains similar to that of individuals from the general population. Active drinkers exhibit more neuroticism, less agreeableness and less conscientiousness than long-term teetotalers. Long-term teetotalism seems to foster a clear amelioration of the personality traits impaired by alcohol, but not a modification of personality. The rational management of emotions appears to be the single key factor of lasting abstinence, via the restoration or the new establishment of defense mechanisms required for coping with challenging situations, and thus seems likely to impose behavior modifications. By focusing on emotions management and its effects on behavior, further studies could eventually identify relevant indicators of treatment success.

This study was funded by a grant from the MILDT (Mission Interministérielle de Lutte contre la Drogue et al Toxicomanie—French Interministerial Office for the Fight against Drugs and Toxicomania).

## Background

The five-factor model (FFM), also known as Big Five, is currently one of the most influential and investigated models used in the personality research field (De Raad & Mlacic, 2015 McCrae, 2011). In Brazil, although the number of studies published using the FFM as reference is relatively small in comparison to other countries (Silva & Nakano, 2011 Passos & Laros, 2014), it can be stated that the development of instruments based on this model is increasing. Among the psychological instruments approved by the Federal Council of Psychology (Conselho Federal de Psicologia, 2017) and available on the Brazilian market, we can cite the NEO Personality Inventory - Revised (NEO-PI-R (Flores-Mendoza, 2007)), the Factorial Battery of Personality (Bateria Fatorial de Personalidade (BFP) in the original (Nunes, Hutz, & Nunes, 2010)), the Factorial Scale of Neuroticism (Escala Fatorial de Neuroticismo, in the original (Hutz & Nunes, 2001)), the Factorial Extraversion Scale (Escala Fatorial de Extroversão, in the original (Nunes & Hutz, 2007a)), and the Factorial Scale of Socialization (Escala Fatorial de Socialização (Nunes & Hutz, 2007b)). In addition to these, there are a number of instruments under development, either for research purposes or for future commercialization (e.g., Andrade, 2008 Carvalho, Nunes, Primi, & Nunes, 2012 Hauck Filho, Machado, Teixeira, & Bandeira, 2012a,b Gomes & Golino, 2012 Hutz et al., 1998 Natividade & Hutz, 2015 Passos & Laros, 2015 Primi, Santos, John, & De Fruyt, 2016 Vasconcelos, 2005 Vasconcellos & Hutz, 2008).

Since the instruments for personality assessment tend to be extensive, usually consisting of more than 100 items, one of the research objectives in this area is the development of reduced scales (Carvalho et al., 2012 Hauck Filho et al., 2012a, b Natividade & Hutz, 2015 Passos & Laros, 2015). The literature shows evidence that a large number of items in an instrument can be a source of measurement error. For example, very long instruments can induce discouragement, fatigue, and inattention in the participants. Furthermore, a large number of items may impede the joint administration of two or more instruments. Therefore, scales with relatively few items can potentially minimize such problems and be useful in different testing settings (e.g., surveys and screenings), provided that they have acceptable reliability indices and satisfactory evidence of validity.

One possible disadvantage of using reduced scales concerns the relatively high amount of measurement errors due to the fact that the number of items of a scale is negatively related to the amount of measurement errors. Another drawback of using reduced scales is related to the possible occurrence of increasing type I and II errors (Credé, Harms, Niehorster, & Gaye-Valentine, 2012). However, the literature already presented evidence that reduced instruments can be a reliable alternative for personality assessment (Donnellan, Oswald, Baird, & Lucas, 2006 Laverdière, Morin, & St-Hilaire, 2013 Rammstedt, 2007). With this motivation, some reduced scales for personality assessment based on the FFM have been proposed in recent years in Brazil.

Andrade (2008), for example, developed the Reduced Inventory of the Big Five Personality Factors (Inventário Reduzido dos Cinco Grandes Fatores de Personalidade (IGFP-5R) in the original), based on the translation and adaptation for Brazil of the Spanish version of the Big Five Inventory (Benet-Martinez & John, 1998). Originally composed of 44 items, the inventory was administered to a sample of 5247 subjects from all Brazilian geographic regions. Confirmatory factor analysis demonstrated the adequacy of a model with 32 items and five correlated factors with reliability coefficients ranging from .66 to .76. By analyzing the items using the item response theory (IRT), the author certified that the instrument had adequate psychometric parameters, even considering that the items did not cover the entire latent trait continuum. Among other conclusions, Andrade (2008) pointed out the need to carry out studies investigating the evidence of the convergent validity between the IGFP-5R and other FFM-based instruments, such as NEO-PI-R and NEO-FFI-R.

Hauck Filho et al. (2012a, b) proposed the reduced marker scale (Escala de Marcadores Reduzidos (EMR) in the original), based on adjective markers for personality assessment identified by Hutz et al. (1998). Analyzing data from a sample of 674 university students, a five-factor structure was found. Each factor was composed of five items, with reliability coefficients of factor scores ranging from .61 to .80. In another study with the EMR on a sample of 208 adolescents Hauck Filho et al. (2012a, b), factor analysis also indicated a five-factor structure with each factor containing four items. The reliability coefficients of the factor scores ranged from .55 to .80. Subsequently, Machado, Hauck Filho, Teixeira, and Bandeira (2014) analyzed the responses of 887 university students to the EMR. Factor analysis pointed to a structure with five oblique factors, and IRT analysis indicated a good adjustment of the measurement model, although with a concentration of the items in a restricted range of the latent trait continuum, as occurred in the study conducted by Andrade (2008). Finally, Pariz, Haddad, and Machado (2016) gathered evidence of convergent and criterion validity regarding the EMR. The results indicated statistically significant correlations between the EMR and the BFP (Nunes et al., 2010), with the exception of the Socialization (i.e., Agreeableness) and the Openness to Experience factors.

Another example is the study conducted by Carvalho et al. (2012) regarding the translation and adaptation to Brazil of the Ten-Item Personality Inventory (TIPI), developed by Gosling, Rentfrow, and Swann (2003). According to Carvalho et al., TIPI is one of the most cited reduced scales based on the FFM. The results of data analysis of a sample of 404 Brazilian adolescents indicated a structure of three factors, but with low reliability indices ranging from .41 to .63. Among other notes, the authors indicated that before discarding the use of the TIPI in the Brazilian cultural context, it is necessary to gather evidence of validity based on external variables, including other instruments constructed based on the FFM.

Natividade and Hutz (2015) elaborated the reduced scale of personality descriptors (Escala Reduzida de Descritores de Personalidade (Red5) in the original), composed of 20 items. In one study, analyses of a sample of 1889 adults resulted in an orthogonal structure with five principal components with reliability coefficients ranging from .59 to .84. In a second study, with a sample of 512 adults, confirmatory factor analysis corroborated the structure obtained in the first study. There was also evidence of convergent validity between the Red5 and the BFP (Nunes et al., 2010).

Finally, Passos and Laros (2015) proposed a semantic differential scale with 47 items, called Reduced Scale of Big Five Personality Factors (Escala Reduzida de Cinco Grandes Fatores de Personalidade (ER5FP) in the original). Exploratory and confirmatory factor analyses with data from a sample of 365 undergraduate students indicated a five-factor structure with 20 items. The reliability coefficients ranged from .71 to .85. The authors concluded that the scale was adequate as a measure of the five factors, considering the sample analyzed. As a research agenda, the authors highlighted the objective of increasing and diversifying the sample (e.g., the inclusion of participants with other levels of education and from all Brazilian geographic regions) and carrying out convergent and criterion validity studies.

In order to contribute to the development of reduced instruments for the assessment of personality based on the FFM and given continuity to the studies of Passos and Laros (2015) and Andrade (2008), the present study has as overall objective obtaining evidence of the convergent validity between the ER5FP and the IGFP-5R. Moreover, this study aimed to test the factorial validity of the two instruments, analyzing the theoretically expected measurement model for the two scales (i.e., five correlated factors). Finally, this study also had the objective of analyzing the role of covariates in the description of the factors that compose the scales.

The covariates gender, age, and level of education were used to carry out comparisons between groups. The covariant sex was chosen based on studies that indicate that there are differences between men and women regarding personality traits (Schmitt et al., 2017 Weisberg, DeYoung, & Hirsh, 2011). Schmitt, Realo, Voracek, and Allik (2008) concluded in their study with data from 55 nations that in more prosperous and egalitarian societies, the personality traits of men and women tend to be less similar. In general, previous findings indicate that women have higher scores on Extraversion, Agreeableness, and Neuroticism (Weisberg et al. 2011). The effect of age on personality traits has also been investigated in several studies (Donnellan & Lucas, 2008 Rammstedt, 2007 Srivastava, John, Gosling, & Potter, 2003). In a study with a reduced version of the Big Five Inventory, the BFI-10, Rammstedt (2007) concluded that younger participants tended to present higher scores on extraversion, while the older ones had the highest scores on Agreeableness and Conscientiousness. Regarding the effect of level of education, the findings in the studies of Rammstedt (2007) indicated that people with higher levels of education tend to present higher scores on Openness to Experience. In addition to the covariates cited above, we also analyzed variables informing marital status (see Boyce, Wood, & Ferguson, 2016) and whether the participant is a parent (see Prinzie, Stams, Deković, Reijntjes, & Belsky, 2009) in order to verify whether there is any association of these two variables with the personality traits assessed by both instruments.

## Results

### Psychological Features assessed by NEO

MANOVA indicated a significant group effect (F = 5.777, P<0.0001). Subsequent one-way ANOVA demonstrated that patients with treatment-resistant depression showed significantly high scores for neuroticism and lower scores for extraversion, openness and conscientiousness on the NEO, compared with healthy controls or patients with remitted depression (Figure 1). Patients in remission showed no significant differences in NEO scores, compared to healthy controls (Figure 1).

In (D) Agreeableness, there is not a significant difference between three groups (F (2,125) = 0.49 P = 0.616). *P<0.01, **P<0.001 compared to control (ANOVA followed by Scheffe test).

The subscales of each domain on the NEO are shown in Table 2. Patients with treatment-resistant depression showed significantly higher scores for anxiety, depression, self-consciousness and vulnerability in the neuroticism subset. They also showed low scores for warmth, gregariousness, assertiveness, activity, excitement-seeking, and positive emotion in the extraversion subset, feelings and actions in the openness subset, modesty in the agreeableness subset, and competent, achievement striving and self-discipline in the conscientiousness subset, compared with remitted depression and healthy control subjects (Table 2).

Neuroticism correlated significantly with HAM-D scores in all MDD patients including both remitted and treatment-resistant groups (neuroticism, r = 0.341, p<0.01 extraversion, r = −0.497, p<0.001). In contrast, there was no correlation between NEO scores and the severity of depression in patients with treatment-resistant depression (data not shown).

A significant negative correlation between neuroticism and extraversion was seen in healthy controls and remitted depression patients, but not in treatment-resistant depression patients (Table 3). Significant positive correlation between extraversion and openness was seen in healthy controls, but not in the remitted depression and treatment-resistant depression groups (Table 3).

### Relationship between scores on the NEO and the TCI in Patients with Treatment-Resistant Depression

As shown in Table 4, there were significant, strong relationships between NEO and TCI factors, in the patients with treatment-resistant depression. Openness on NEO correlated positively with reward dependence and cooperativeness in TCI. Similarly, agreeableness on the NEO correlated positively with reward dependence and cooperativeness on TCI. Neuroticism on the NEO showed positive correlation with harm avoidance and negative correlation with self-directedness and cooperativeness on the TCI. Extraversion on the NEO correlated negatively with harm avoidance and positively with reward dependence and persistence on the TCI. Conscientiousness on the NEO showed negative correlation with harm avoidance and positive correlation with persistence and self-directedness on the TCI.

## Chapter 11: The APIL and TRAM learning potential instruments in South Africa

AUTHOR/S: T. Taylor

ABSTRACT: This chapter covers three main topics involving the APIL and TRAM learning potential instruments developed by Aprolab, namely, the underlying theory, the nature and contents of the instruments and technical information. Early theory by Vogotsky, Feuerstein and others suggested that learning potential is solely reflected in the zone of proximal development, the degree to which an individual’s performance improves with intervention. APIL and TRAM instruments are based on a broader theory drawn from cognitive psychology, information processing theory and learning theory. This theory incorporates four main elements – fluid intelligence, information processing efficiency, transfer and learning rate. The first two constructs are static (not direct measures of learning potential, but nevertheless critical to learning). The last two dimensions are dynamic (direct measures of learning). Only learning rate is related to the zone of proximal development concept from which the learning potential construct originally arose. There are actually three Aprolab learning potential instruments: APIL, TRAM-2 and TRAM-1. They cover the educational spectrum from no education to tertiary education. All of them are based on the theory mentioned above and incorporate separate measures of the four constructs listed above. In some cases the constructs are broken down into sub-dimensions. APIL has eight scores, TRAM-2 six and TRAM-1 five. The sub-dimensions are described, the techniques whereby the raw-scores are converted into normed scores on these sub-dimensions explained, and examples of stimulus material provided. The APIL and TRAM instruments have been used since the mid-90’s. Technical information is given on scale inter-correlations, reliabilities, predictive and concurrent validity, and culture-fairness/lack of bias.

## Discussion

This investigation used several large, international samples to correlate and partially behaviorally validate the relationship between four proposed primary temperament dimensions and their proposed brain systems. The study looked at five behavioral variables, including: gender level of education religious preference political orientation and the degree to which an individual regards sex as essential to a successful relationship. We did not measure brain chemistry, but rather used behavioral characteristics correlated with brain chemistry in previous studies. Thus the results may be consistent with the overall proposed relationship between brain chemistry and the four dimensions, but they are not proof of these associations.

### Sex Differences on the Analytic/Tough-Minded and Prosocial/Empathetic scales

Males and females scored in the predicted direction for the Analytic/Tough-minded and Prosocial/Empathetic scales in North America and also in six other countries tested, including both Western and Eastern societies. Importantly, a sample from a university population (rather than a dating site) showed the same results, with even greater odds ratios for the Analytic/Tough-minded and Prosocial/Empathetic dimensions, and odds ratios closer to one for the other two dimensions. There were sex differences for some of the other scales, but these were exceptionally small (e.g., r = 0.004 for the Cautious/Social Norm Compliant scale in the North American sample).

These data are consistent with the hypothesis that the Analytic/Tough-minded scale measures some influence by the testosterone system, and the Prosocial/Empathetic scale measures some influence by the estrogen/oxytocin system. These data are also consistent with the results of two fMRI studies using the FTI (Brown et al., 2013). The FTI Analytical/Tough-minded scale co-varied with activity in regions of the occipital and parietal cortices associated with visual acuity and mathematical thinking, attributes linked with testosterone testosterone also contributes to brain architecture in these areas. Further, the FTI Prosocial/Empathetic scale co-varied with activity in regions of the inferior frontal gyrus, anterior insula, and fusiform gyrus. These are regions associated with mirror neurons or empathy, a trait linked with the estrogen/oxytocin system. The effect sizes in this study were relatively small but many other influences from biological, cultural and epigenetic forces play a role in temperament and behavior.

Interestingly, the highest percentage of Analytical/Tough-minded men and women were from Spain (47.2% 24.8%) and the highest percentage of Prosocial/Empathic men and women were from Japan (25.8% 52.2% Table 1), even though Japan had the most men in the sample (72%). These data suggest that different cultures are composed of individuals who, collectively, express somewhat different temperament profiles, at least those who wish to find a dating partner.

### Level of Education

We predicted that Level of Education would be correlated with the Curious/Energetic scale because attaining a higher academic degree requires elevated curiosity, motivation and energy (Subotnik et al., 2011), qualities linked in the biological literature with the dopamine system (Depue and Collins, 1999 Zuckerman and Kuhlman, 2000 Wacker et al., 2006). As hypothesized, the Curious/Energetic scale showed a small but significant positive correlation with Level of Education, while the other FTI scales showed a negative correlation or minimal to no effect.

Supplementary support for this association between the Curious/Energetic scale of the FTI and the dopamine system is suggested by correlations with the NEO-FFI: We found a high correlation between the FTI Curious/Energetic scale and the Openness to Experience domain of the Big Five the relevance of this is that the Openness domain is also positively associated with level of education and may be linked with activity in the dopamine system (DeYoung and Gray, 2009). Further, two fMRI investigations (Brown et al., 2013) have shown that higher scores on the Curious/Energetic scale co-varied with activity in brain regions linked with dopamine activity.

The above results support the hypothesis that the Curious/Energetic scale of the FTI measures, to some degree, the influence of the dopamine system.

### Religious Affiliation

Individuals scoring highest on the Cautious/Social Norm Compliant scale were significantly more likely to be members of an organized religious community. The effect size was small, but the direction of the effect was different from that of the other three scales of the FTI. These results are consistent with our hypothesis that the Cautious/Social Norm Compliant scale may measure, to some degree, serotonergic factors, because genetic data associate aspects of the serotonin system with religiosity (Lorenzi et al., 2005 Ott et al., 2005) and traditionalism (Golimbet et al., 2004).

### Political Orientation

It was predicted that participants who scored highest on the Cautious/Social Norm Compliant scale would be more politically conservative because self-reported conservatives in other western countries score higher than self-reported liberals on scales of respect for authority and tradition (Graham et al., 2009), characteristics of the Cautious/Social Norm Compliant dimension. Also, traditionalism is linked in the biological literature with aspects of the serotonin system (Golimbet et al., 2004). Consistent with the prediction, political conservatism was positively associated with high scores on the Cautious/Social Norm Compliant scale.

It was also predicted that participants who scored highest on the Prosocial/Empathetic scale would be significantly more liberal in their political views, because self-reported liberals in dozens of countries score higher than conservatives on scales of caring/nurturance (Graham et al., 2009), qualities associated in the biological literature with the estrogen and oxytocin systems (Knickmeyer et al., 2006). Consistent with the prediction, political conservatism was negatively associated with high scores on the Prosocial/Empathetic scale. These data further support other research that variability in political values is not simply attributable to differences in cognitive style, but is also, in part, associated with differences in biological factors (Alford et al., 2005 Amodio et al., 2007 Kanai et al., 2011).

### Sex as Essential to a Relationship

It was predicted that scores on both the Analytical/Tough-minded scale and the Curious/Energetic scale would positively correlate with the statement, “Sex is an essential part of a successful relationship” because elevated activity in the testosterone and dopamine systems is widely associated with elevated sex drive (Bagatell et al., 1994 Meston and Frohlic, 2000) and we reasoned that those individuals with a higher sex drive would be more likely to regard sex as important to a successful partnership. These predictions were supported.

Further, since higher central serotonin regularly suppresses sexual desire and sexual function (Rosen et al., 1999), we also predicted that higher scores on the Cautious/Social Norm Compliant scale would negatively correlate with the statement, “Sex is an essential part of a successful relationship,” because individuals with a lower sex drive might regard sex as less important to a successful partnership. Scores on the Cautious/Social Norm-Compliant scale did show a negative correlation with the statement, “Sex is an essential part of a successful relationship.”

### Comparison with the NEO-FFI

We compared responses on the FTI with those on the NEO-FFI (the shortened form of the NEO-Personality Inventory Costa and McCrae, 1992), not only to assess the criterion validity of the FTI using an established measure but also to further explore the potential characteristics linked with the FTI scales. Our three predictions were supported. Moreover, this comparison suggested several qualities associated with the FTI that we had not previously associated with this measure.

#### Curious/Energetic Scale

The Openness to Experience domain of the NEO-FFI and the Curious/Energetic scale of the FTI were positively correlated (r = 0.308, p = 0.000015). As both attempt to measure exploratory behavior, novelty-seeking and curiosity (Costa and McCrae, 1992 Depue and Collins, 1999), this positive correlation was anticipated. Interestingly, the Openness to Experience domain of the NEO-FFI is also the only domain of the Big Five that has shown a consistent, positive correlation with general intelligence (DeYoung et al., 2005), while the Curious/Energetic scale of the FTI is positively correlated with level of education. This suggests convergent data for these two dimensions. But it also suggests that the Curious/Energetic scale of the FTI may measure some aspect of general intelligence, as well as level of education.

The Extraversion scale of the NEO-FFI and the Curious/Energetic scale on the FTI represented the strongest positive correlation between the two measures (r = 0.519, p = 1.7 × 10 -19 ). Perhaps because the Extraversion domain of the NEO-FFI is associated with risk-taking and energy (Depue and Collins, 1999), consistent with the dopamine system (Cohen et al., 2005 DeYoung and Gray, 2009), these qualities are consistent with those of the Curious/Energetic scale on the FTI.

The Curious/Energetic Scale demonstrates convergent validity with the NEO-FFI domains of Openness to Experience and Extraversion. This is meaningful, as Extraversion scores have been positively correlated with the volume in the medial orbitofrontal cortex (Omura et al., 2005 Rauch et al., 2005), a brain area associated with coding the hedonic value of reward (DeYoung et al., 2010). While the Openness to Experience domain has been positively correlated with parietal areas predictive of working memory and the control of attention (DeYoung et al., 2010), it is also the only Big Five trait associated with intelligence (DeYoung et al., 2005). The Curious/Energetic scale of the FTI is positively correlated with the substantia nigra (Brown et al., 2013), an important brain area involved in the reward path, and is significantly correlated education level. These data suggest that high scores on the Curious/Energetic scale of the FTI may measure some form of Extraversion and Openness/Intellect.

#### Cautious/Social Norm Compliant Scale

It was anticipated that scores on the Cautious/Social Norm Compliant scale of the FTI would correlate with the Conscientious scale of the NEO-FFI because both the NEO-FFI domain of Conscientiousness and the Cautious/Social Norm Compliant scale on the FTI attempt to measure self-control and self-regulation (Costa and McCrae, 1992), as well as the desire to plan and organize (DeYoung and Gray, 2009). These two scales were significantly correlated in a positive direction (r = 0.461, p = 2.2 × 10 -11 ), showing convergence. Additionally, a positive correlation was found between the FTI Cautious/Social Norm Compliant scale and the Neuroticism scale of the NEO-FFI (r = 0.170, p = 0.019), perhaps suggesting that caution and the desire to conform to social rules can be linked with anxiety in social situations.

#### Analytic/Tough-minded Scale

The prediction that higher scores on the Analytical/Tough-minded scale of the FTI would correlate negatively with high scores on the Agreeableness scale of the NEO-FFI was supported. We anticipated this relationship because tough-mindedness is likely to be the opposite of tender-mindedness, a trait in the Agreeableness domain of the NEO-FFI. There was, however, an unanticipated positive correlation between the Analytic/Tough-minded scale of the FTI and the NEO-FFI domain for Conscientiousness (r = 0.224, p = 0.0019). Perhaps this correlation is indicative of a mutual sense of purpose, determination, attention to detail and will to achieve (Costa and McCrae, 1992). The unanticipated positive correlation found between the Analytic/Tough-minded scale of the FTI and the NEO-FFI scale for Openness to Experience (r = 0.241, p = 0.0008) may also derive from these shared attributes.

#### Prosocial/Empathic Scale

Consistent with the literature (McCrae et al., 2000 Costa et al., 2001 Chapman et al., 2007), women scored higher on the NEO-FFI domains of Neuroticism and Agreeableness. They also scored higher on the Prosocial/Empathic scale of the FTI than the men (r = 0.373, p = 1.2 × 10 -7 ).

In contrast to our prediction that Agreeableness and the Prosocial/Empathic scale of the FTI would be positively correlated, there was not a significant relationship. This scale divergence is interesting since Agreeableness is essentially the prosocial domain of the NEO. Though Agreeableness is not associated with empathy in the NEO, it does measure compliance, trust, modesty, tolerance and tender-mindedness (Costa and McCrae, 1992). In fact, in a recent study of personality and brain activity during emotional attribution decisions, participants with higher Agreeableness scores also showed greater right temporoparietal junction activity, a brain region associated with perspective-taking and Theory of Mind (Haas et al., 2015), qualities thought to contribute to the empathy. However, since empathy was not formerly associated with Agreeableness, the HEXACO personality model included a facet called Emotionality to specifically address empathy, attachment, and harm-avoidance (Ashton and Lee, 2007). Further, when the FTI was administered as part of two fMRI studies (Brown et al., 2013), participants with higher scores on the Prosocial/Empathic scale showed greater activity in the inferior frontal gyrus, anterior insula and fusiform gyrus, regions associated with estrogen binding and empathic behavior, suggesting that the Prosocial/Empathic scale does measure qualities of the domain of Agreeableness associated with the NEO and the empathy/attachment measure of Emotionality in the HEXACO.

Last, the Prosocial/Empathetic scale of the FTI was positively correlated with the NEO-FFI scale of Openness to Experience (r = 0.284, p = 0.0001) and negatively correlated with the NEO-FFI scale for Conscientiousness (r = -0.242, p = 0.0008).

### Novel Aspects and Potential Advantages of the FTI

The FTI was not developed to replace other measures of personality. It does not measure neuroticism or extraversion, for example. But based on the results of our convergent and discriminant analyses, the modest length of the FTI and its additional constructs of empathy, tough-mindedness and degree to which one regards sex as essential to a partnership, the FTI may be a useful complement to the NEO-FFI or other Five Factor Models of personality.

The novel value of the 56-item FTI within a business or organizational context may be to highlight individual differences in style of communication, style of leadership, preference for rules and schedules, attitude toward risk, tendency to trust, sensitivity to rank, degree of emotional containment, tendency toward traditionalism, degree of linguistic and/or mathematical creativity, and proficiency at executive social skills. The potential value of the FTI in a personal context may be to lend additional insight into attitudes of friends, partners, and kin regarding their political and religious presuppositions, their educational aspirations, and their views regarding the importance of sex to a relationship (an important component of partnership viability) and partner–partner and parent𠄼hild compatibility. The potential value of the FTI to the science of personality is that it is derived directly from brain architecture and physiology, providing an additional way to look at the core structure of temperament. Last, this additional approach may be able to simplify temperament explanations and uses. For example, with the rationale that dopamine and its receptors strongly influence behavior, some of the domains from linguistically derived questionnaires like the BFI that uses Extraversion and Openness to Experience might be collapsed into one domain and thus simplified. Thus, physiology and behavior based on hormonal and neurotransmitter influences may be able to cover a broader spectrum than several other constructs. In short, the FTI may provide a parsimonious construct.

Anecdotal evidence suggests that the FTI is useful in a variety of spheres. A public service group has initiated a project that uses the FTI to match foster parents with foster children a major American accounting firm has used the FTI to train 45,000 employees on how to structure conversations and presentations with potential clients. The largest international Internet dating service is using the FTI to enable members to better understand their likely compatibility with potential life partners currently 14 million men and women in 40 countries have taken the questionnaire for purposes of insight. A major international credit card company has used the FTI to further understand their card users and couples therapists are using the FTI to enable couples to understand their differences and solve ingrained issues. These users have anecdotally reported (to HEF) that the FTI is easy to explain, understand, and apply.

### Limitations

The functional significance of the statistically significant but small effect sizes is yet to be determined. These quantitative differences may not translate into relevant behavioral differences between individuals or groups. Conversely, these small effect sizes may be an accurate representation of these four biological systems, largely because these systems are subject to many physiological interactions with one another, with other biological systems, and with social and epigenetic forces that contribute to phenotypic variations in temperament. Moreover, other studies show very small size effects and suggest that the small effect sizes reported in this paper are appropriate and could be meaningful (de Moor et al., 2010).

Further, it has been argued that almost any data will be significant using a large sample. But statistically significant differences are not inevitable with large samples. They only appear if there is an effect in the population, and they indicate that the effect would still be found with replication. Large samples provide the opportunity to find small but significant effects that normally would be overwhelmed by statistical noise. In fact, small effect sizes are not unusual for studies of large populations (de Moor et al., 2010).

Another limitation is that for the analyses, random samples of the population were not used instead, the samples were largely based on unmarried individuals who were looking for a partner, who had access to a computer, who were willing to pay to join an Internet dating site, and who felt comfortable using an online dating service. This is why it was important that the basic sex findings were replicated in a university sample as well.

However, the Internet population we tested represents a significant and important group. Over one–third of the adult U.S. population is single (over 100 million individuals) and with a current divorce rate exceeding 45%, almost half of Americans have been or are likely to become single at some point in their lives (Taylor et al., 2011). The populations examined in this study represent a large and growing percentage of the broad U.S. population and those of several other countries. Subjects also ranged in age from 18 to 88 years they were from every major ethnic group (e.g., European American, African American, Asian American, and Latino) they lived in rural, suburban and urban areas and they resided in all 50 states in the U.S., as well as in Canada and six additional cultures, both Eastern and Western.

Last, participants may have skewed their responses to enhance their social desirability. However, participants responding to any questionnaire that uses self-appraisals will approach the task with an array of subliminal and cognitive agendas that cannot be fully screened. In fact, the correlation analyses and the Eigen analysis of the FTI samples are more comprehensive than the samples used in most psychological studies that canvas the attitudes and behaviors of college populations paying a large fee for college entrance, coming largely from similar backgrounds, of the same general age, and sharing similar life styles and life goals.

### Future Directions

To further explore the FTI measure, an investigation is underway to assess the relationship between 63 specific alleles and the four FTI temperament dimensions. The essential study of test–retest reliability of the FTI is in preparation as well. To apply these data to life situations, we examined the role of these proposed temperament dimensions in initial mate choice (Fisher, 2009 Fisher et al., 2010b) this investigation continues. Further research could also explore how these four broad proposed styles of thinking and behaving effect one’s proneness to divorce, adultery, and other social, reproductive, cognitive, affective and/or motivational processes, as well as their varying expression in different cultures, different age groups, different occupations, and among those of different sexual orientations and those with different medical conditions.

One promising field for future investigation may be exploration of the possible relationship between these temperament dimensions and specific psychiatric diseases, due to accumulating data associating several psychiatric syndromes with specific neural substrates. For example, perhaps individuals primarily expressive of the Curious/Energetic scale are disproportionately susceptible to substance abuse, because several of the primary addictions are linked with activity in the mesolimbic dopamine system (Fowles, 2001 Dawe et al., 2004 Loxton et al., 2011). They may also be predisposed to diseases linked with mania, including bipolar affective disorder and the schizophrenia spectrum. These diseases have been linked with alterations in the activities of the catecholamines (Kapura et al., 2005 Dalley and Roiser, 2012 Kang et al., 2013) and dopamine antagonists reduce some of the symptoms of these conditions (Ginovart, 2012). Also, traits associated with types of Attention Deficit Hyperactivity Disorder (ADHD) have been linked with imbalances in the dopamine and norepinephrine systems (Zametkin, 1987), as well as a specific allele in the dopamine receptor D4 gene (Faraone et al., 2001). The testosterone system has been associated with diseases in the Autism Spectrum (Geschwind and Galaburda, 1985 Baron-Cohen and Hammer, 1997 Baron-Cohen et al., 2005), so those expressive of the Analytical/Tough-minded scale may be predisposed to these. The testosterone system is also associated with aggressiveness, so individuals expressive of this temperament dimension may be disproportionately susceptible to violent or anti-social behavior (Nyborg, 1994). Last, activity in the estrogen system is commonly linked with clinical depression (Stahl, 1998), perhaps predisposing those expressive of the Prosocial/Empathetic scale of the FTI to anxiety and depression.

Regardless of the many studies linking aspects of various diseases with neural systems, no single neurotransmitter or hormone system is likely to be responsible for the full array of symptoms in any disease pattern. Instead, a multitude of factors influence how each of these neural systems impact one another, affect other neural systems, modifiers and genomic activational events, and contribute to cognitive and behavioral outcomes. Much further investigation is necessary to establish substantive links between the temperament dimensions of the FTI and specific bio-behavioral illnesses.

## Results

### Profile Agreement

We began by computing profile agreements rP between self- and other-ratings for all 4115 participating dyads. Expectedly, when we used raw scores, mean profile correlations were relatively high (Table 1, first row). The mean value across all four samples was 0.57 (see the last column). When distinctiveness was separated from normativeness (by standardizing scores), profile agreement dropped by 0.16 points, on average. This suggests that distinctive agreement accounted for approximately 77, 73, 70, and 70% of overall profile agreement in the Czech, Estonian, Flemish, and German samples, respectively. However, individual profile correlations based on standardized scores were not always lower than those relying on raw scores. For 15.1% (Estonian sample) to 21.7% (Flemish sample) of all dyads, profile correlations based on standardized scores were higher, not lower, than the same correlation based on raw scores.

Table 1. Mean profile correlations and Rank Consistency Indices for the four samples.

Analogously to standardizing scores trait- or column-wise, it is also possible to standardize scores person- or row-wise. Sometimes this type of standardization is called ipsatization, which is useful for eliminating peculiarities in a rater's style of responding (e.g., preference for one part of the response scale). As a result of ipsatization, the mean is zero, and the standard deviation is one, for each person. To standardize scores trait-wise and person-wise simultaneously, it may be necessary to iterate the standardization procedure along columns and rows several times to obtain column and row means and standard deviations sufficiently close to zero and one, respectively. The third row in Table 1 reports mean profile correlations based on double-normalized scores for our four samples. Obviously, these profile correlations are very similar to those in the previous row.

### Trait Agreement

Next, we computed self-other agreement for all NEO-PI facet scales. It should be noted that linear transformations of trait variables (adding, and multiplying by, a constant) do not affect their correlation. Figure 1 demonstrates the trait agreement values (Pearson rT) in our four samples for all 30 NEO-PI traits. The shape of these four profiles is similar: Their correlations across facets vary from 0.51 (Czech vs. Flemish) to 0.73 (Flemish vs. Estonian), suggesting that the pattern of agreement is generalizable from one language and/or culture to another. This indicates that individuals and their informants agree on some traits more than on others. For example, E3: Assertiveness is a trait on which it is easy to agree (average rT = 0.56), whereas perceptions of self and informant on O6: Values agree least (average rT = 0.32). The mean agreement across all traits varied from 0.32 (Germany) to 0.47 (Estonia), which is quite consistent with previously reported values (McCrae et al., 2004).

Figure 1. Profiles of self-other trait correlations for the Czech, Estonian, Flemish, and German samples.

It is perhaps interesting to mention that it made little difference whether the Spearman rank-order correlation or the Pearson r was used. Self-other trait correlations computed on ranks were, on average, only slightly smaller than the Pearson correlations.

### Rank Consistency Index

Next, we decomposed self-other trait correlations into contributions by individual dyad, using the RnkCI, and computing ρ XY -values for all 4115 dyads. As expected, the mean ρ XY-values (across all traits) were similar to the profile correlations of the same self-other dyads. The correlations between ρ XY and rP were 0.75, 0.79, 0.51, and 0.67 for the Czech, Estonian, Flemish, and German samples, respectively. Although these correlations are relatively high, there is still a fair amount of freedom until a complete congruence. We therefore checked whether these correlations got higher by aggregating them over a sufficient number of occurrences (Epstein, 1979, 1980). We divided all samples into 10 approximately equal-sized groups on the basis on their profile agreement values rP. Figure 1 displays the mean values of profile correlation ( r P) and the mean RnkCI ( ρ XY) for these 10 groups.

Except for very few deviating points, the relationship is almost perfectly linear, suggesting that, if random noise is suppressed, profile correlations can be rather accurately predicted from mean differences in the ranking on personality traits. The correlation between the data points is 0.96 (p < 0.0001). If the individual (X) and the informant (Y) report sufficiently similar ranks on all, or at least many, personality traits, the two profiles are similar as well. The effects of aggregation show that most of the unexplained variance is indeed random because it is canceled out by the aggregation.

### Contribution of Traits to Profile Agreement

We can also ask what each trait contributes to the self-informant profile correlation. Let us suppose that, in each individual profile, scores are replaced by their ranks: The NEO-PI facet scale scoring the highest receives a rank of one. The next highest score receives a rank of 2, and so on, until the lowest score receives a rank of 30. Self and informant scores are ranked separately. Now the difference between ranks for self- and other-ratings determines how much this particular trait contributes to the overall profile correlation. Traits which have identical or similar ranks in self and informant profiles contribute more strongly to profile correlation than those traits which have a large discrepancy between ranks. Thus, we can apply the same Rank Consistency Index or RnkCI ρXY to evaluate how much each trait contributes to profile correlations.

For each individual dyad, we found 30 ρXY-values, each showing how much a particular trait contributed to the profile correlation. After that, we computed the mean consistency value ρ XYf for each trait by averaging scores across all N self-informant pairs in each of our four samples. This averaged RnkCI indicates how much this particular personality trait contributes to the profile correlation averaged across all participants in that sample. This allows us to check if the contributions of that trait to profile agreement are related to the self-other agreement rT for that trait (as reported in Figure 2). The correlation between ρ XY and rT was 0.79, 0.80, 0.54, and 0.87 for Czech, Estonian, Flemish, and German samples, respectively. For greater clarity, we illustrate the relationship between ρ XY and rT for the combined sample of 4115 targets in Figure 3.

Figure 2. Relationship between average profile correlation (rP) and average RnkCI ( ρ XY), when samples were divided into 10 groups of equal size on the basis of their profile correlations.

Figure 3. The relationship between traitwise self-informant agreement and the contribution of the trait to the average profile correlation.

This figure shows that traits showing higher self-other agreement are the same traits as those contributing significantly to the self-other profile correlations. The average correlation between contributions to profile agreement ( ρ XY) and rT was sufficiently high, r = 0.78, p < 0.0001. For example, E3: Assertiveness, C2: Order, and O2: Aesthetics are high on both axes. At the same time, N4: Self-Contentiousness, O6: Ideas, and A2: Straightforwardness contributed relatively modestly to both measures of agreement. Nevertheless, it is useful to note that both values are in a relatively narrow corridor, somewhere around the value 0.40. This means that relatively good agreement is achievable on all traits without clear distinctions between dimensions that are more or less judgeable.